Back when I was a tender 20 years of age, I spent a couple of months backpacking around Europe, accompanied by my brand-new Discman and a couple of those fold-out wallets of carefully-packed CDs. I needn’t have bothered bringing all of them, though, because pretty much all I listened to was The Clash. I was young, skinny and idealistic, full of political fire and keen to see the world.

The other thing taking up space in my backpack for those months – at the expense of sensible things like shirts and clean socks – was a copy of Hugh Thomas’s The Spanish Civil War, which I’d purchased after listening to The Clash’s ‘Spanish Bombs’ about a million times. Thomas’s book is an exhaustively researched and wonderfully well written tome that’s generally (and rightfully) acknowledged as the best history of the conflict that presaged the Second World War and granted prize fascist lunatic Francisco Franco totalitarian power over Spain for four decades. I read the book as I made my way around Spain, revelling in the country’s culture and its remarkably cheap beer.

The reason I’ve spent this week recalling these times is because on Friday I went and visited the International Centre for Photography’s new-ish exhibition The Mexican Suitcase. It’s a scarcely believable treasure trove of photographic documentation of the Spanish Civil War, hundreds of images taken by photographers Robert Capa, David Seymour and Gerda Taro (who was killed near Madrid in 1937, the first female photojournalist to be killed in the course of covering a war). The negatives were discovered in a suitcase (hence the exhibition’s title) in Mexico City – the gallery’s <a href=”http://museum.icp.org/mexican_suitcase/story.html”>website</a> goes into exhaustive and fascinating detail as to exactly how they might have ended up there.

For anyone with even a passing interest in the story of a war that is compelling both in its narrative and its historical resonance, this is compulsory viewing – despite the ICP’s best efforts to make it otherwise. The gallery has chosen to present the negatives in their entirety, which in theory is an excellent idea: it allows you to see the context in which published images were taken, and also to see how the photographers went about documenting what they saw. Unfortunately, the ICP has gone about doing this by basically tacking a bunch of proof sheets up on the wall, which even with the magnifiers provided makes for a tedious viewing experience – the images you’re looking at are so small that it’s impossible to make out details and subtleties. This is a shame, because there’s lots and lots to see – 127 rolls’ worth of photos, to be precise.

But such minor quibbles aside, this is still a hugely important exhibition for a number of reasons. For a start, Capa, Seymour and Taro’s trips to the front were pioneering examples of what we today call photojournalism. The negatives give us an insight into how they approached this new style of journalism – the instant hand-held cameras they used allowed a far more dynamic approach than the large-format cameras that preceded them, but still, they chose their targets carefully, composed their shots painstakingly, and rarely took more than a few frames of any one scene.

The volume of images allows us to compare and contrast the photographers’ styles (particularly two rolls that find Capa and Taro depicting pretty much exactly the same subject matter). And they give us a large volume of photographic documentation of Spain during the war that would end in four decades of military rule and international isolation. There are unseen images of some of its most famous moments and figures – images from the battle of Teruel, a portrait of Republican leader Dolores Ibarruri, a snap of Ernest Hemingway hanging with Republican soldiers – and also of the nameless people who bore the brunt of the conflict, the ordinary Spaniards who were caught up in a war that would leave divisions that lasted generations. As such, perhaps the most moving images of the entire exhibition are Taro’s shots of a morgue in Valencia after an air raid – pictures that were taken barely two months before her own death.

Honestly, The Mexican Suitcase is the sort of show that it’s a privilege to have a chance to see. And as a bonus, there’s also a fantastic exhibition about the Cuban revolution on downstairs. We really are spoilt in NYC sometimes.